I used Tamiya's Clear coat on my propeller today and got an unpleasant surprise. It's a shiny finish, not a matte finish. This is not a show stopper because a shiny propeller is not going to stick out nearly as much as a shiny finish on a flat yellow tail and horizontal stab. Does the Tamiya Flat Base work well as a matte finish coat over decals?

Tamiya flat base is not designed to be used by itself. Instead, it's meant to be mixed into a gloss paint so that it becomes flat. In your case, just mix up a little of your clear coat with the flat base to get a clear flat. You can control how flat the final finish will be by varying the ratio of flat base to clear coat.

As with everything, practise on a dead model first before trying something new on your latest masterpiece

Well, as it says "Clear Coat" it is of course clear/shiny/glossy and not matte. DO NOT try Tamiya Flat Base instead of a matte coat. It´s only for mixing it with glossy Acrylic (Tamiya-)paints (same as Mr. Hobby FlatBase) to get them flat - otherwise you will ruin your Decals with a white/milky cover.

Greets T.

OK, Jessica was faster ...
T.

Humbrol Matt Cote is good if you can get it.

note that you can mix the flat base with the clear coat to get a matt clear finish. experiment first tho

You can also mix Tamiya flat base with Future. Works really well.

Thanks all. This is why I like it here.